| **Legal Proceedings and Contingencies**            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Legal Proceedings And Contingencies [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Legal Proceedings and Contingencies                | Legal Proceedings and Contingencies From time to time, as a normal incident of the nature and kind of businesses in which we are, and were, engaged, various claims or charges are asserted and litigation or arbitration is commenced by or against us arising from or related to matters, including but not limited to: product liability; personal injury; patents, trademarks, trade secrets or other intellectual property; labor and employee disputes; commercial or contractual disputes; strategic acquisitions or divestitures; the prior sale or use of former products allegedly containing asbestos or other restricted materials; breach of warranty; or environmental matters. Claimed amounts against us may be substantial but may not bear any reasonable relationship to the merits of the claim or the extent of any real risk of court or arbitral awards. We record accruals for losses related to those matters against us that we consider to be probable and that can be reasonably estimated. Gain contingencies, if any, are recognized when they are realized and legal costs generally are expensed when incurred. At September 29, 2017, our accrual for the potential resolution of lawsuits, claims or proceedings that we consider probable of being decided unfavorably to us was not material. Although it is not feasible to predict the outcome of these matters with certainty, it is reasonably possible that some lawsuits, claims or proceedings may be disposed of or decided unfavorably to us and in excess of the amounts currently accrued. Based on available information, in the opinion of management, settlements, arbitration awards and final judgments, if any, which are considered probable of being rendered against us in litigation or arbitration in existence at September 29, 2017 are reserved against or would not have a material adverse effect on our financial position, results of operations or cash flows.Environmental Matters We are subject to numerous U.S. Federal, state, local and international environmental laws and regulatory requirements and are involved from time to time in investigations or litigation of various potential environmental issues. We are responsible, or are alleged to be responsible, for ongoing environmental investigation and remediation of multiple sites, including as a result of our acquisition of Exelis. These sites are in various stages of investigation and/or remediation and in some of these proceedings our liability is considered de minimis. We have received notices from the U.S. Environmental Protection Agency (“EPA”) or equivalent state or international environmental agencies that a number of sites formerly or currently owned and/or operated by us or companies we have acquired, and other properties or water supplies that may be or have been impacted from those operations, contain disposed or recycled materials or wastes and require environmental investigation and/or remediation. These sites include instances where we have been identified as a potentially responsible party under the Comprehensive Environmental Response, Compensation and Liability Act (commonly known as the “Superfund Act”) and/or equivalent state and international laws. For example, Exelis received notice in June 2014 from the U.S. Department of Justice, Environment and Natural Resources Division, that it may be potentially responsible for contribution to the environmental investigation and remediation of multiple locations in Alaska. In addition, the EPA issued on March 4, 2016, a record of decision selecting a remedy for the lower 8.3 mile stretch of the Lower Passaic River. The EPA’s selected remedy included dredging the river bank to bank, installing an engineered cap and long-term monitoring. The EPA estimated the cost of the cleanup project will be $1.38 billion. On March 31, 2016, the EPA notified over 100 potentially responsible parties, including Exelis, of their potential liability for the cost of the cleanup project but their respective allocations have not been determined. We have found no evidence that Exelis contributed any of the primary contaminants of concern to the Passaic River. We intend to vigorously defend ourselves in this matter and we believe our ultimate costs will not be material. Although it is not feasible to predict the outcome of these environmental claims, based on available information, in the opinion of management, any payments we may be required to make as a result of environmental claims in existence at September 29, 2017 are reserved against, covered by insurance or would not have a material adverse effect on our financial position, results of operations or cash flows. |

| X                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Legal Proceedings And Contingencies [Abstract]
+ References
No definition available.
+ Details**Name:**hrs_Legalproceedingsandcontingenciesabstract**Namespace Prefix:**hrs_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The entire disclosure for legal proceedings, legal contingencies, litigation, regulatory and environmental matters and other contingencies.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -URI http://asc.fasb.org/topic&trid=2127136
+ Details**Name:**us-gaap_LegalMattersAndContingenciesTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |